Different prognostic association of systolic blood pressure at different time points with postdischarge events in patients hospitalized for decompensated heart failure

Background The association of systolic blood pressure (SBP) with mortality in heart failure (HF) patients is paradoxical, and the time points of baseline SBP are also different across prior studies. We hypothesized that the levels of SBP at admission and at discharge had different associations with postdischarge events. Methods The study population included patients hospitalized for decompensated HF in the Heart Failure Center of Fuwai Hospital from January 1, 2009 to December 31, 2014. The primary outcome was a composite of cardiovascular (CV) death and heart transplantation. Multivariate Cox proportional-hazards and restricted cubic spline analyses were used to assess the relationships between SBP at different time points and outcomes. Results In total, 2005 patients were included with a median follow-up of 48.4 months. The median age was 59 years, and 69.9% were male. Multivariate Cox analyses showed that compared with SBP < 105 mmHg, higher SBP at admission was associated with better long-term primary outcome (105-119 mmHg, HR = 0.764, P = 0.005; 120.134 mmHg, HR = 0.658, P < 0.001; >= 135 mmHg, HR = 0.657, P = 0.001). Patients whose discharge SBP was higher than 135 mmHg had a similar primary outcome as those with SBP < 105 mmHg (HR = 0.969, P = 0.867), and the results remained unchanged even after adjusting for admission SBP (HR = 1.235, P = 0.291). The results of restricted cubic spline analysis indicated similar associations. Conclusions Lower but not higher SBP at admission is associated with more CV deaths/heart transplantations (a reverse J-shaped curve). In contrast, there is a U-shaped association between discharge SBP and CV mortality/heart transplantation.